Well packer



M. B. CONRAD June 19, 1956 WELL PACKER 2 Sheets-Sheet l Filed April 2, 1954 rroeA/E ys.

M. B. CONRAD June 19, 1956 WELL. PACKER 2 Shams-Shea?I 2 Filed April 2, 1954 INVENTOR. MART/N B. CQMQAQ BY MMM rv-oQ/VE Ys.

United States Patent O WELL PACKER Martin B. Conrad, Downey, Calif., assignor to Baker Oil Tools, Inc., Los Angeles, Calif., a corporation of California Application Apnl 2, 1954, serial No. 420,586

17 claims. (ci. 16s- 121) lThe present invention relates to subsurface well tools, and more particularly to packers to be anchored in packed-olf condition is well bores.

An object of the present invention is to provide an improved retrievable well packer that can be anchored in packed-oft condition in a well casing, or similar well conduit, merely by applying pressure to the fluid in the packer, and without the necessity for further electing relative movement of any parts of the packer.

Another object of the invention is to provide a well packer embodying a packing structure to seal against the wall of a well conduit and gripping elements to anchor the packer to the well conduit, the packer being simple in construction, capable of withstanding very high pressures, and being actuatable merely by subjecting it to hydraulic pressure.

A further object of the invention is to provide a well packer embodying a rubber or rubber-like packing element for sealing against the wall of a well conduit, which is encompassed by a gripping structure for anchoring the packer to the well conduit, in which the gripping structure is effective to prevent cold owing of the packing material from the sealing region in the well conduit, especially under high pressure or high temperature operating conditions, or both.

Still another object of the invention is to provide a well packer to be lowered in a well bore on a string of tubing which can be anchored in packed-oit` condition in a well conduit merely by applying pressure to the fluid internally of the tubing and packer, and which is releasable from the well conduit merely by relieving the pressure within the tubing and packer, or by applying a greater pressure externally of the tubing and packer. l'n a more limited sense, the invention contemplates a well packer of the aforementioned character, in which reverse pumping or circulation of fluid down the tubing will not only release the packer from the well conduit, but can also ow around the exterior of and back into the interior of the well packer. for upward passage through the tubing.

Yet another object of the invention is to provide a well packer to 'oe lowered in a well bore on a tubing string through which liuid under pressure is to be pumped, in which any tendency for the tluid pressure to elevate the tubing string is eliminated, or at least minimized considerably.

Yet a further object of the invention is to provide a well packer and control valve combination to lbe lowered in a well bore on a tubing string, the control valve determining the passage of 'uid between the interior and exterior of the tubing string as a result of manipulating the tubing string, in which the valve is easily shiftable from closed to open position despite the presence of a high-or any pressure dilerential in the tubing string and well packer.- Preferably, the control valve is hydraulically balanced to permit movement from closed to open position regardless of the pressure conditions within the tubing string and well packer.

Another object of the invention is to provide a well packer and control valve combination to be lowered in a well bore on a tubing string, in which an excess of uid pressure externally of the tubing string and control valve will eifect automatic opening of the control valve.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the present specification. It will now be described in detail, for the purpose of illustrating the general principles of the invention, but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best delined by the appended claims.

Referring to the drawings:

Figure l is a combined longitudinal section and side elevational View of an embodiment of the invention, with the parts disposed in the relative positions that they may occupy for lowering or elevating the apparatus in a well casing or similar well conduit;

Fig. 2 is a view similar to Fig. l, disclosing the valve mechanism in closed position;

Fig. 3 is a View similar to Fig. l, disclosing the well packer anchored in packed-oil' condition within a well casing;

Fig. 4 is a cross-section taken along the line 4 4 on Fig. 3;

Fig. 5 is a cross-section similar to Fig. 4, with the parts in another relative position.

As disclosed in the drawings, a 'well packerA is adapted to be moved longitudinally in a well casing B to and from a location in which it is to be anchored therein in packedofi condition. The well packer includes a tubular body 10 having a downwardly facing shoulder 11, from which a skirt portion 12 depends. A pliant, elastic packing 13, which is specilically in the form of a tubular rubber packing member, is secured to the skirt portion 12 of this tubular body. A connecting ring 14 is molded to the upper end of the packing 13, and this ring is threaded into the body skirt 12, with both the ring 14 and the upper end of the packing 13 abutting the shoulder 11, thereby rmly securing the packing to the tubular body 10.

The lower portion 15 of the pliant, elastic packing 13, which may be made of rubber or rubber-like material, extends outwardly and is adapted to sealingly and slidably engage the wall of the well casing B. Such slidable and sealing engagement occurs substantially at all times during lowering of the well packer A in the well casing to the desired point or location at which the well packer is to be anchored in packed-off condition. The lower portion 15 of the packing has an inner surface 16 flaring in a downward direction, so that uid acting thereon will urge the lower portion of the packing more firmly into sealing engagement with the wall of the well casing. The outer surface 17 of the lower packing portion `15 is also preferably inclined in a downward and outward direction, so that fluid under pressure acting in a downward direction thereon will tend to urge the lower portion of the packing inwardly out of sealing engagement from the wall ofthe well casing B.

When pressure is applied internally to the packing 13,

such pressure is utilized not only to obtain a lluid tight upper portion 19 and has a plurality of circumferentially spaced, longitudinal slots 20 extending from said upper portion completely through its lower end to provide a plurality of gripping dogs or legs 21 normally occupying an inward position out of anchoring engagement with f 3 the wallof the well casing B, but which are capable of being deflected in an outward direction into anchoring engagement with the casing; To enhance such anchoring, the outer surfaces` of the, gripping dogs are provided with wickers or teeth 22 adapted to dig into the casing wall;

The upper portion 1 9k of the grippingsleeve 13v extends upwardly into a supporting sleeve 23 threaded onto the skirt 12 of the body 1b. TheA circumferentiallyk continuous portion i9 of the gripping sleeve is connected tothe support 23 by being threaded thereinto to the extent determined by engagement of the upper end of the portion-19 with the lower end` of the body skirt 12. The lower portion ofthe supporting sleeve 23 has its inner surface 24 aringin a downward direction, to avoidv interference with the outward deilection of the gripping dogs or legs 2i into engagement with the wall of the well casing B.

From the structure described so far, it will be evident that the application of pressure internally of the packing 13 will urge the latter in an outward direction, and cause itto force the gripping dogs 21 outwardly into engagement with the wall of the well casing B. Under high pressure or high temperature operating conditions the rubber packing material might tend to be deformed into the spaces or slots 2b between adjacent gripping dogs, and maynot retract from such position. To avoid this potential difficulty, a backing sleeve 25 is interposed between the gripping sleeve 18 and the rubber packing sleeve 13. Thus, the backing sleeve has au upper circumferentially continuous portion 26 threaded into the lower end of the skirt 12 of the tubular body 10, thebacking sleeve being provided with circumferentially spaced longitudinally extending slots 27 opening through itslower end which are staggered with respect to the slots Ztl. in the gripping sleeve 18, to provide a plurality of legs 28 that can deflect in a lateral direction both inwardly and outwardly with respect to the well casing B, Actually, the terminal portions 29 of the backing sleeve legs 28 are inclined in a downward and outward direction, being engageable with companion inclined surface 17 of the packing sleeve and extending under correspondingly inclined terminals 3) of the gripping dogs 21.r By virture of the terminal portions'29 of the backing sleeve 25, the longitudinal slots 2d in-the gripping sleeve 18 are closed at their lower ends.

When pressure is applied to the fluid within the tubular body i and the packing sleeve 13, the main portion of theflatter behind the gripping and backing sleeves-13, 25 is'urged in an outward direction by such fluid pres.-` sure,` carrying the legs 28 of the backing sleeve and the dogs Z1 in an` outward direction, to anchor the gripping dogs 21 in the wall of the well casing. When the pressure is relieved, then the backing sleeve legs 2S and the grippingdogs Z1inherently retract with respect to the well casing. thelower portion of the packing 13, which is in sealing engagement with the weil casing, tending to shift the packing sleeve 13 Vand the packer body 19 in an upward direction. However, such tendency is forestalled by the gripping-engagement of the dogs 21 in the well casing. Theiubber material at the lower end 1S of the packing cannot move in an upward direction, since such movement is precluded by theterminal 29 of the backing sleeve and by the. gripping dogs 2l themselves. There is no; through passage remaining for the rubber packing material to flow into, as under high pressure or high temperature conditions. Outward movement: of the packingmaterialis blocked by the backing sleeve dogs 2S. The. passage of the material under high pressure ortempenature -conditions into the slots 27 between the backing..-sleeve dogs .is limited, since such material will merely engage the gripping dogs 2.1 that overlie the backing sleeve slots. Similarly, any tendency for the'packing material tofmoveinen .upwardfdirectioninto-the slots or spacesy The fluid pressure will also be acting upon 4, between the terminals 29 of the backing sleeve legs 28 is limited "by engagement of such material with the lower ends 30 of the dogs 21, which bridge such slots or openings. Actually, by virtue of the inclined surface Contact 17, 29 between the packing sleeve 13 and the terminal portions 29 of the backing sleeve dogs, the uid pressure in an upward direction tends to urge the backing sleeve and the dogs 21 more iirmly in an outward direction to secure the dogs to the well casing.

When` it is; desiredrto release thelwell packerV A from' the well casing, it isv merely necessary to relieve the pressure within the tubing string C, to which the packer is attached, `andiin theywellpacker itself, or to provide an excess of pressure around the packing 13 and the gripping and backing sleeveslS'; 25', which will force the elements 21, 23 in an inward direction. The fluid under pressure moving in a downward direction aruond the well packer will alsoact onthe inclined surface 17 of: the packing and shift .its lower portionv 15 away from the wall of thef well casing, allowing the uid to move past such lower .porf tion and backinto the packing sleeve, and through the tubular body 10, for continued upward passage through the tubing string C to the top of the well bore.

In the particular tool disclosed in the drawings, it is desired to relieve the tubing string C of any hydraulic forces exertingan elevating action thereon, and it is also desiredto provide a controlivalve D for enabling fluid to pass between;the `interior and the exterior of the wellV packer withoutthe necessity for moving around the packing sleevek 13. As shown; in the drawings, the-control valve Dis interposed between thetubular body 10 andthe tubing string C itself. Thus, a lower valve housing or body 40 is threaded onto the upper end of the tubular bodyy 10, this-lower valve housing having an inwardly directed upper shoulder 41 extending above and engaged by aretainer Vring-d2. whose'lower portion 43 engages andembracesga=rubber or rubber-like seal ring 44, provided with a lower portion confined by a lower retainer ring'45 restinguponA the upper end of the tubular body` 1t). The retainerfrings 4.12, 4S, in-eiect, are opposed to one another, embracing the upper and lower portions of the seal ring 44 and leaving a substantial intermediate portion offtheilatter exposed for sealing action against a companion valve head 46 formed at lthe lower end of a `tubular mandrel or inner member 47 threadedly connectedxto the lower end of the tubing string C. Leakage4V offluid Abetween the lower valve body and tubular packer bodyis prevented, by theprovision of a suitable thread seal l48 betweenthemembers, whereasleakage between theupper retainer ring 42 and lower valve body 4i) is preventedby a suitable side seal 49 mountedinv the former and engaging the'inner wall of the latter.

The control valve `D further includes an upper valve housing-or body 50 threaded onto the upper end of 'the'l lower valveY housing or body 40 and having aplurality" of circumferentiallyA spaced side or circulation portsSl therein, specifically disclosed'in the drawings as being immediately above the upper end of the lower valve body orhousing di). This upper valve body 56 is threaded onto the lower end of a ratchet enclosing sleeve 52 which is, in turn, threaded ontov the lower portion of a cap S3 surrounding and closely adjacent the periphery of the tubular fmandrel- 47,' which extends upwardiy 'therefrom The'periphery of themandrel 47 is provided witha plurality of 'circumferential ratchet teeth 54 facing ina downward direction and engageable with companion internal ratchet teeth 55, facing in an upward direction, formed on a slit ratchet ring 56 disposed within the ratchet sleeve. The ratchet ring 56 is engageable with the lower end of the-cap-53 and lhas an external surface 57tapering in adownward direction for engagement withca'com-- panion tapered `internal'surfaceSS in the v'ratchet sleeve;`

When vthe ring 56-'is in an upwardpositlonsubstantially in engagement with the capv 53,' a lateral ,space'exists betweenltheexterior of lthe ring and the inclined surface 58 of the ratchet sleeve 52, allowing the ring 56 to be expanded to a sufficient extent as to bring its teeth 55 out of engagement with the companion teeth 54 on the tubular mandrel 47. On the other hand, when the ring 56 is in a downward direction relative to the sleeve 52, it will be wedged into engagement with the tapered surface 58 in the sleeve and held in coupling engagement with the ratchet teeth 54 of the tubular mandrel, in order to lock the latter to the ratchet sleeve 52 and to the valve housing 50 itself.

The ratchet teeth 54, 55 are so designed that the mandrel teeth will engage the ring teeth when the mandrel 47 is moved in a downward direction, in order to prevent downward movement of the mandrel with respect to the ratchet sleeve and valve housing, unless purposely desired. However, the mandrel 47 is free to move upwardly within the ratchet ring 56 and with respect to the valve housing 50, the ratchet ring being merely displaced laterally during such upward movement of the mandrel.

Whenever it is desired to move the mandrel 47 from an elevated position with respect to the Valve housing 50 to a lower position, the ring 56 is expanded so that its teeth 55 no longer can engage the mandrel teeth 54. Such expansion is accomplished by causing one end of the ring at one side of its split to engage a stationary stop element 59 secured to the ratchet sleeve 52. The other end of the ring 56 has a key 60 suitably secured to it and extending inwardly into a longitudinally extending keyway 61 formed in the tubular mandrel 47 When the mandrel 47 is in the position disclosed in Fig. 4 with respect to the ratchet ring 56, the latter is contracted into locking engagement with the teeth 54 of the mandrel. However, upon rotation of the mandrel in a counterclockwise direction or to the left, such as shown in Fig. 5, one end of the keyway 61 will engage the key 60 to tend to shift the ring 56 circumferentially of the ratchet sleeve 52. The other end of the ring 56 engages the stationary stop element 59 and cannot move. As a result, arcuate movement of the mandrel 47 expands the sleeve 56 and shifts its ratchet teeth 55 out of a position where they can engage the companion teeth 54 on the mandrel. Upon such arcuate movement of the mandrel 47, it can be lowered with respect to the ratchet sleeve 52 and body 50.

In order to secure such expansion of the ratchet ring 56, it is necessary to prevent arcuate movement of the ratchet sleeve 52. This is accomplished by a friction drag device 62, which may be mounted on the tubular body of the well packer. Thus, the tubular body 10 has a plurality of circumferentially spaced, longitudinal slots 63 therein, in which friction drag blocks 64 are slidable, the outer surfaces of these blocks being frictionally engageable with the wall of the well casing B. Theyare urged in an outward direction by a plurality of compression springs 65 bearing against the bottom' of each slot 63 and also against the blocks 64 themselves. Outward movement of the blocks is limited by engagement of their terminal portions 66 with upper and lower stop rings67 encompassing the body. The lower ring 67 may be secured to the body 10 against longitudinal movement, as through use of screws 68.

The springs 65 urge the friction drag blocks 64 into engagement with the wall of the well casing B, thereby resisting both rotational and longitudinal movement of the tubular body 10, as well as of the valve housing 40, 50 and ratchet sleeve 52 connected thereto. The friction force of the blocks 64 against the well casing B is more than suicient to prevent the ratchet sleeve 52 from rotating, and, therefore, allows the'tubular mandrel 47 to be turned With respect to the sleeve 52 for the purpose' of expanding the ratchet ring 56 out of a position ofv engagement with the mandrel.

The tubular mandrel 47 embodies the generally cylindrical valve head 46 at its lower portion, which is mov.- able downwardly into sealing engagement with the seal ring 44 whenever the circulation ports 51 are to be closed,

and which is movable upwardly out of engagement with such seal `ring 44 whenever the circulation ports 51 are to be opened. This relative upward and downward movement is permitted, since the friction drag blocks 64 will resist longitudinal movement of the valve housing 40, 50 in the well casing.

Thus, by raising or lowering the tubular mandrel 47, it is possible to open or close the ports 51 to the passage of uid between the interior of the well packer A and tubing string C and the exterior thereof.

Assuming that the tubular mandrel 47 is in its downward position with its valve head 46 in sealing engagement with the companion seal 44, in order to close the circulation ports 51, and that uid under pressure is being pumped down through the tubular string C, such fluid under pressure is acting across the lower end 69 of the tubular mandrel, and, in fact, across an effective area of the mandrel 47 equal to the cross-sectional area within the seal ring 44, tending to elevate the mandrel 47 with respect to the packer body 10 and valve housing 40, 50. This action also tends to elevate the tubular mandrel 47 to a valve opening position.

Such hydraulic shifting tendency is counterbalanced and offset in the present instance. An annular piston 70 is formed on the mandrel 47 above its lower valve head 46, which is slidably engageable with a cylindrical wall 71 in the valve housing 50 above the circulation ports 51. The cylinder 71 has a substantially greater diameter than the internal diameter of the seal ring 44 and the external diameter of the valve head 46. The mandrel 47 above the piston 70 is reduced in diameter and is slidable along an inwardly directed flange 72 of the valve housing. The tubular mandrel 47 can be elevated with respect to the valve housing 50 to a position limited by engagement of the upper end of the piston 70 with the lower end of the ange 72, the mandrel being lowered with respect to the valve housing to a position determined by engagement of a shoulder 73 above the valve head 46 with the upper end of the lower valve housing 40, in which position the periphery of the valve head 46 is in full sealing engagement with the seal ring 44.

The iluid under pressure within the tubular mandrel 47 is permitted to enter the annular space 74 between the cylindrical Wall 71 and the periphery of the tubular mandrel 47 thereabove. Thus, one or more side ports 75 are provided through the mandrel immediately above its piston portion 70, to allow iluid to move into the cylindrical space 74 and act downwardly upon the piston and in an upward direction upon the flange 72. Leakage of fluid in a downward direction between the piston 70 and the cylindrical Wall 71 is prevented by a suitable side seal 76, such as a rubber 0 ring, contained within a piston groove 77 and slidably and sealingly engageable with the wall 71 ofthe cylinder. Similarly, a suitable side seal 78, such as a rubber O ring, is `contained within an internal groove 79 inthe flange 72, being slidably and sealingly engageable with the periphery of the mandrel 47 above the side port or ports 75.

As was pointed out above, the uid under pressure is acting over the cross-sectional area S at the lower end of the valve head 46, including the area of the passage therethrough, tending to -elevate the mandrel 47. This same uid under pressure passes outwardly through the side port or ports 75 into the cylindrical space 71, and acts in a downward direction over the area R of the annular piston 70. -This latter annular area R is preferably made equal to the area S at the lower end of the valve head 46. Accordingly, any hydraulic forces acting over the area S and tending to elevate the tubular mandrel 47 are counterbalanced and oiset by the same hydraulic forces acting in va downward direction over the area yR.

Assuming that the control valve is in closed position, such as shown in Figs. 2 and 3, with pressure being imposed on the tluid within the tubing string C, the control valve D can easily be shifted to open position merely by arancia elevating the tubular mandrel 47. The friction drag blocks 64 prevent corresponding elevation of the parts below and surrounding the tubular mandrel, so that the mandrel is easily lifted to open the circulation ports 51 in the valve housing, as shown in Fig. l.

With fluid under pressure within the tubing string C and the tool D, A, there is no tendency for the mandrel to be elevated and inadvertently open the valve D, in view of the counterbalancing annular piston 7i). As a matter of fact, even in the absence of any circulation ports 51, the counterbalanced mandrel areas R, S would still be effective to eliminate any hydraulic forces acting on the mandrel 47 tending to elevate it, as well as the tubing string C, in the Well casing B.

The apparatus is assembled and run in the well casing` preferably with the mandrel 47 in its upper position, as shown in Fig. l, in which the circulation ports 51 are open. Fluid can readily by-pass the tool during its lowering in the well casing by flowing upwardly through the packing sleeve 13 and tubular body 10, then discharging in an outward direction through the open circulation ports 51, as well as passing upwardly through the mandrel 47 and into the tubing string C. During such downward movement, the lower portion 15 of the rubber packing or swab cup 13 is slidably and sealingly engaging the wall of the well casing B. In view of the absence of a pressure diierential within the packing sleeve 13, the gripping dogs 21 and back-up sleeve legs 28 are disposed in a retracted position, such as shown in Fig. 1. The ratchet sleeve 56 will engage the tubular mandrel 47, to prevent downward movement of the mandrel with respect to the valve body 50 and tubular packer body 1i).

When the location in the well casing B is reached at which the tool is to be anchored in packed-off condition,

the tubing string C and mandrel are turned to the left,

the ratchet ring 56 being expanded, as shown in Fig. 5, to remove its teeth 55 from engagement with the mandrel teeth 54, whereupon the mandrel 47 can be lowered with respect to the valve housing 50 and packer body 10 into the position disclosed in Fig. 2, in which the valve head 46 is in sealing engagement with the seal ring 44 of the valve, closing the circulation ports 51. Thereafter, the lluid in the tubing string C and Well tool A may be subjected to pressure, such fluid under pressure acting within the packing sleeve 13 to urge it in an outward direction and expand the backing sleeve legs 28 and the dogs 21 outwardly, to place the latter in anchoring engagement with the Well casing. The fluid under pressure also insures the holding of the lower portion 1S of the packing sleeve in firm sealing engagement with the well casing B. As pointed out above, the overlapping arrangement between the backing sleeve legs 28 and the gripping dogs Z1 precludes flowing of the rubber material through the various slots 20, 27, insuring that the rubber packing sleeve will remain intact and available for the performance of its sealing function. Any suitable fluid under pressure may now be pumped down the tubing string C and through the well packer A for displacement in the Well bore at some region below the packing sleeve 13, as through perforations or a casing shoe therein (not shown). Any tendency for the lluid under pressure to dislodge the packing 13 is resisted by the iluid pressure itself acting within the rubber packing sleeve and holding the gripping dogs 21 in anchoring engagement with the wall of the well casing. As pointed out above, such fluid under pressure has no tendency to elevate the mandrel 47, in view of the provision of the counterbalancing annular piston 70.

At any time, and even with pressure within the tubing string C and tool A, the control valve D can be shifted to an open position merely by elevating the tubular mandrel a7, thereby allowing the pressure both internally and externally of the tool to be equalized. Upon such equalizing, which could also occur merely by relieving the internal pressure within the tubing stringv C and the wellpacker A, there is no pressure differential within the packing sleeve 13 available to hold the gripping elements 21 in anchoring engagement with the wall of the well casing. Accordingly, these gripping elements will be released, which will then allow the entire well packer A to be moved longitudinally in the Well casing B to a new location, or removed entirely from the well bore. Even with the valve D remaining in closed position, uid can be pumped down the annulus between the tubing C and casing B. and this fluid will automatically move the gripping elements 18 to a retracted position, and will press upon the upper inclined surface 17 of the packing sleeve 13, to retract it from the well casing, allowing the fluid to flow around the lower end of the packing and back into the interior of the well packer A, for continued upward movement through the tubing string C to the top of the well bore. in this manner, any excess cement slurry that might remain in the tubing string C and Well packer A can be pumped back to the top of the well bore for suitable disposition.

As a matter of fact, the reverse pumping of fluid down through the tubing-casing annulus in the manner dcscribed above is effective to shift the valve D to open position. Such iluid under pressure will pass through the circulation ports 51 and will act in a downward direction over the area of the lower valve housing 4l) and also over the annular area of the upper valve housing 5t), shifting the valve housing and tubular packer body 10 in a downward direction with respect to the mandrel 47, thus opening the circulation ports 51. This downward movement occurs easily and without restraint from the ratchet ring 56, since the latter will merely ratchet freely over the companion teeth S4 on the periphery of the tubular mandrel 47. Accordingly, with the circulation ports 51 open, part of the fluid being pumped down around the outside of the tubing string C will flow into the circulation ports 51 for upward passage through the tubular mandrel 47 and tubing string C, whereas the remaining portion of the Huid will continue on down around the exterior of the well packer A, past the lower end 15 of the packing sleeve 13, for return movement up through the interior of the packing sleeve 13, tubular body 10, tubular mandrel 47, and tubing string C, to the top of the well bore.

An any time, it is merely necessary to take an upward strain on the tubular mandrel 47, which will open the circulation joint D, eliminating the pressure differential within the well packer A, which allows the gripping elements 21 to retract from anchoring engagement with the well casing B, whereupon the entire tool can be ele-` vated to the top of the hole.

The inventor claims:

1. In a well packer: tubular body means adapted to be lowered in a Well casing', a exible sleeve carried by said body means; a plurality of circumferentially adjacent gripping members disposed around said sleeve and having external teeth to grip the casing; a plurality of circumferentially adjacent backing members interposed between and engageable with said sleeve and gripping members, said backing members being staggered with respect to said gripping members to bridge the spaces between adjacent gripping members and prevent said sleeve from passing into said spaces; the interiors of said sleeve and body means being in fluid communication with each other to cause lluid under pressure within said body means and sleeve to expand said sleeve and cause said sleeve to expand said backing members and gripping members outwardly to engage said gripping members with the casing.

2. In a well packer: tubular body means adapted to be lowered in a .well casing; a pliant, elastic packing sleeve carried by said body means and having a portion slidably and sealingly engageable with the casing; a plurality of circumferentially adjacent elongate gripping members disposed around said sleeve to one side of said portion and having external teeth to grip the casing; a plurality of circumferentially adjacent elongate backing members disposed to one side of said portion and interposed between and engageable with said sleeve and gripping members, said backing members being staggered with respect to said gripping members to bridge the spaces between adjacent gripping members to prevent said sleeve from passing into said spaces; the interiors of said sleeve and body means being in fluid communication with each other to cause Huid under pressure within said body means and sleeve to expand said sleeve and cause said sleeve to expand said backing members and gripping members outwardly to engage said gripping members with the casing.

3. In a well packer: tubular body means adapted to be lowered in a well casing; a pliant, elastic packing sleeve carried by said body means and having a portion slidably and sealingly engageable with the casing; a plurality of circumferentially adjacent elongate gripping members disposed around said sleeve to one side of said portion and having external teeth to grip the casing; a plurality of circumferentially adjacent elongate backing members disposed to one side of said portion and interposed between and engageable with said sleeve and gripping members, said backing members having lateral projections between said sleeve portion and the ends of said gripping members, said backing members and their projections being staggered with respect to said gripping members to bridge the longitudinal and transverse spaces between adjacent gripping members and prevent said packing sleeve from passing into said spaces; the interiors of said sleeve and body means being in fluid communication with each other to cause iluid under pressure within said body means and sleeve to expand said sleeve and cause said sleeve to expand said backing members and gripping members outwardly to engage said ygripping members with the casing.

4. In a well packer: a tubular body adapted to be lowered in a well casing; a packing sleeve carried by said body and having a portion slidably and sealingly engageable with the casing; a gripping sleeve carried by said body and surrounding said packing sleeve to one side of said portion, said gripping sleeve having a plurality of longitudinal circumferentially spaced slots providing laterally movable gripping members having external teeth to grip the casing; a backing sleeve carried by said body and disposed between said packing sleeve and gripping sleeve to one side of said portion, said backing sleeve having a plurality of longitudinal, circumferentially spaced slots providing laterally movable backing members; said backing sleeve slots being staggered with respect to said gripping sleeve slots; said backing members having lateral projections between said packing sleeve portion and the ends of said gripping members; said packing sleeve and body being in fluid communication with each other to cause uid under pressure within said body and packing sleeve to expand said packing sleeve and cause said packing sleeve to expand said backing members and gripping members outwardly to engage said gripping members with the casing.

5. In a well packer: a tubular body adapted to be lowered in a well casing; a pliant, elastic sleeve carried by said body; a gripping sleeve carried by said body and surrounding said elastic sleeve, said gripping sleeve having a plurality of longitudinal, circumferentially spaced slots providing laterally movable gripping members having external teeth to grip the casing; a backing sleeve carried by said body and disposed between said elastic sleeve and gripping sleeve, said backing sleeve having a plurality of longitudinal, circumferentially spaced slots providing laterally movable backing members; said backing sleeve slots being staggered with respect to said gripping sleeve slots; said elastic sleeve and body being in fluid communication with each other to cause fluid under -10 pressure within said body and elastic sleeve to expand said elastic sleeve and cause said elastic sleeve to expand said backing members and gripping members outwardly to engage said gripping members with the casing.

6. In a well packer: a tubular body member to be lowered in a well bore; packing means on said body member sealingly engageable with the wall of the well bore; means carried by said body member and engageablewith the wall of the well bore to anchor said tubular body member thereto; a tubular member connectible to a running-in string and telescopically arranged in leakproof relation with respect to said body member; means providing an enclosed annular cylinder space between said body member and tubular member; means for feeding fluid under pressure from the interior of one of said members to said cylinder space; said tubular member having a portion subject to the pressure of iiuid in said cylinder space to exert a downward force on said tubular member.

7. In a well packer: tubular body means to be loweredA in a well bore; packing means on said body means sealingly engageable with the Wall of the well bore; means carried by said body means and engageable with the well bore wall to anchor said tubular body means thereto; a tubular member connectible to a running-in string and telescopically arranged in leakproof relation within said body means; means providing an enclosed annular cylinder space betweensaid rbody means and tubular member; means for feeding fluid under pressure from the interior of said tubular member to said cylinder space; said tubular member having a first portion subject to the pressure of fluid in said tubular member to exert a lifting force on said tubular member; said tubular member having a second portion in said cylinder space subject to the pressure of fluid in said cylinder space to exert a downward force on said tubular member.

8. In a well packer as defined in claim 7; wherein the cross-sectional areas of said rst and second portions are substantially equal.

9. In a well packer: a tubular body memberV to .be lowered in a well bore; packing means on said body member sealingly engageable with the wall of the well bore; a tubular member connectible to a running-in string and telescopically arranged in leakproof relation with respect to said body member; means providing an enclosed annular cylinder space between said body member and tubular member; means for feeding fluid under pressure from the interior of one of said members to said cylinder space; said tubular member having a portion subject to the pressure of iluid in said cylinder space to exert a downward force on said tubular member.

10. In a well packer: tubular body means to be lowered in a well bore; packing means on said body means sealingly engageable with the wall of the well bore; a tubular member connectible to a running-in string and telescopically arranged in leakproof relation within said body means; means providing an enclosed annular cylinder space between said body means and tubular member; means for feeding fluid under pressure from the interior of said tubular member to said cylinder space; said tubular member having a iirst portion subject to the pressure of fluid in said tubular member to exert a lifting force on said tubular member; said tubular member having a second portion in said cylinder space subject to the pressure of fluid in said cylinder space to exert a downward force on said tubular member.

l1. In a well packer as defined in claim 10; wherein the cross-sectional areas of said first and second portions aresubstantially equal.

12. In a well packer: tubular body means to be lowered in a well bore; a packing on said body means sealingly engageable with the wall of the well bore; instrumentalities carried by said body means and engageable with the wall of the well bore to anchor said tubular body means thereto; tubular means connectible to a running-in string and telescopically arranged with respect to said body means; coengageable valve instrumentalities on said body means and tubular means operable by said tubular means between open and closed positions to control uid ow between the interior and exterior of said tubular means and body means; means providing an enclosed annular cylinder space between said body means and tubular means; means for feeding uid under pressure from the interior of one of said means to said cylinder space; said tubular means having a portion subject to the pressure of uid in said cylinder space to exert a downward force on said tubular means.

13. In a well packer: tubular body means to be lowered in a well bore; a packing on said body means sealingly engageable with the wall of the well bore; tubular means connectible to a running-in string and telescopically arranged with respect to said body means; coengageable valve instrumentalities on said body means and tubular means operable by said tubular means between open and closed positions to control uid flow between the interior and exterior of said tubular means and body means; means providing7 an enclosed annular cylinder space between said body means and tubular means; means for feeding fluid under pressure from the interior of one of said means to said cylinder space; said tubular means having a portion subject to the pressure of uid in said cylinder space to exert a downward force on said tubular means.

14. In a well packer: tubular body means to be lowered in a well bore; packing means on said body means sealingly engageable with the wall of the well bore; instrumentalities carried by said body means and engageable with the well bore wall to anchor said tubular body means thereto; tubular means connectible to a running-in string and telescopically arranged in leakproof relation within said body means; coengageable valve instrumentalities on said body means and tubular means operable by said tubular means between open and closed positions to control fluid between the interior and exterior of said tubular means and body means; means providing an enclosed annular cylinder space between said body means and tubular means; means for feeding fluid under pressure from the interior of said tubular means to said cylinder space; said tubular means having a rstportion subject tof the pressure of uid in said tubular means to exert a lifting force on said tubular means; said tubular means having a second portion in said cylinder space subject to the.

pressure of luid in said cylinder space to exert a downward force on said tubular means.

15. In a well packer: tubular body means to be lowered in a well bore; packing means on said body means sealingly engageable with the Wall of the well bore; tubular means connectible to a running-in string and telescopically arranged in leakproof relation within said body means; said body means having a side outlet; coengageable valve means on said body means and tubular means below said outlet engageable with each other upon lowering of said tubular means within said body means to prevent fluid iiow through said outlet between the interior and exterior of said tubular means and body means; means providing an enclosed annular cylinder space between Said body means and tubular means; means for feeding fluid under pressure from the interior of said tubular means to said cylinder space; said tubular means having a first portion subject to the pressure of fluid in said tubular means to exert a lifting force on said tubular means; said tubular means having a second portion in said cylinder space subject to the pressure of fluid in said cylinder space to exert a downward force on said tubular means.

16. In a well packer as dened in claim 14; wherein the cross-sectional areas of said rst and second portions are substantially equal.

17. In a well packer as delined in claim 15; wherein the cross-sectional areas of said rst and second portions lare substantially equal.

References Cited in the file of this patent UNITED STATES PATENTS 

1. IN A WELL PACKER: TUBULAR BODY MEANS ADAPTED TO BE LOWERED IN A WELL CASING; A FLEXIBLE SLEEVE CARRIED BY SAID BODY MEANS; A PLURALITY OF CIRCUMFERENTIALLY ADJACENT GRIPPING MEMBERS DISPOSED AROUND SAID SLEEVE AND HAVING EXTERNAL TEETH TO GRIP THE CASING; A PLURALITY OF CIRCUMFERENTIALLY ADJACENT BACKING MEMBERS INTERPOSED BETWEEN AND ENGAGABLE WITH SAID SLEEVE AND GRIPPING MEMBERS, SAID BACKING MEMBERS BEING STAGGERED WITH RESPECT TO SAID GRIPPING MEMBERS TO BRIDGE THE SPACES BETWEEN ADJACENT GRIPPING MEMBERS AND PREVENT SAID SLEEVE FROM PASSING INTO SAID SPACES; THE INERIOR OF SAID SLEEVE AND BODY MEANS BEING IN FLUID COMMUNICATION WITH EACH OTHER TO CAUSE FLUID UNDER PRESSURE WITHIN SAID BODY MEANS AND SLEEVE TO EXPAND SAID SLEEVE AND CAUSE SAID SLEEVE TO EXPAND SAID BACKING MEMBERS AND GRIPPING MEMBERS OUTWARDLY TO ENGAGE SAID GRIPPING MEMBERS WITH THE CASING. 